The present invention relates to measurement of flow of a process fluid in an industrial process. More specifically, the present invention relates to measuring a cross-section of a flow path.
In industrial processes, it is common to measure the flow rate of a process fluid flowing through a conduit. Typically, the flow rate varies across a cross-section of the conduit. Thus, to obtain an accurate measurement of the flow rate, measurements must be taken at different cross-sectional positions within the conduit. Traditionally, such cross-sectional measurements were made by traversing a pitot along a diameter of the conduit. At each of a plurality of positions along the traverse, a pressure reading is taken that is used to determine the flow rate at that position.
Pitot traverses are sometimes performed at a location where an averaging pitot tube is to be inserted to calibrate the output of the averaging pitot tube. An averaging pitot tube provides an average pressure difference between an upstream section of the tube and a downstream section of the tube across a cross-section of the conduit. Averaging pitot tubes typically have a different profile from pitot tubes used to perform pitot traverses and as such interfere with the flow in a different way than the pitot tubes used to perform the pitot traverse. As a result, the pitot traverse may provide a less accurate measure of the cross-section of the flow path when an averaging pitot tube is present and thus may not provide accurate calibration data.
The discussion above is merely provided for general background information and is not intended to be used as an aid in determining the scope of the claimed subject matter. The claimed subject matter is not limited to implementations that solve any or all disadvantages noted in the background.